The objectives of the proposed research is a continuing study of factors which may be responsible for the observed loss of cardiac contractility in congestive heart failure. This project is utilizing the cardiomyopathic hamster in which the active transport "ionic pumps" in the sarcolemma and sarcoplasmic reticulum are being investigated. In addition, the possible role of Taurine (2 amino-ethane sulfonic acid) in the failing heart is being investigated.